1. Field
The present disclosure relates generally to creating a stereoscopic modeling system based on perceptual constraints of a modeled viewer, and more specifically to creating a stereoscopic modeling system based on a maximum divergence angle for a modeled viewer.
2. Related Art
Cinematographic-quality computer animation has evolved to produce increasingly realistic and engaging visual effects. One way that this is accomplished is through the use of stereoscopic filming techniques that simulate human binocular vision by presenting slightly different viewpoints of a scene to a viewer's left and right eye. This technique, also known colloquially as “3D,” can be used to enhance the illusion of depth perception and make objects in a computer-generated scene appear to extend outward from a two-dimensional screen.
In normal human binocular vision, each eye views the world from a slightly different perspective. The difference in the view from each eye, also called parallax, is caused, in part, by the spatial separation between the eyes. The brain is able to combine the different views from each eye and use the parallax between views to perceive the relative depth of real-world objects.
Computer animation stereoscopic filming techniques take advantage of the brain's ability to judge depth through parallax by presenting separate images to each eye. Each image depicts a computer-generated object from a slightly different viewpoint. The distance between the left and right images displayed on a screen (parallax) indicates the relative depth of the displayed computer-generated object. Parallax can be positive or negative depending on whether the computer-generated object appears to be behind the screen (positive parallax) or if it appears to be in front of the screen (negative parallax).
To predict how the computer-generated object will be perceived by a viewer, a stereoscopic modeling system may be constructed that accounts for the position of the computer-generated object within the scene, the stereoscopic filming parameters, and the position of a modeled viewer with respect to a modeled display screen. For example, one type of stereoscopic modeling system may include a stereoscopic transformation that produces a stereoscopically transformed geometry based on the geometry of the computer-generated object. The resulting stereoscopically transformed geometry can be used to assess the quality of a computer-generated scene and provide feedback for the scene director or film maker.
To increase the stereoscopic effect, in some cases, it may be desirable to increase the positive parallax or the distance between the left and right images that are presented to the viewer. In some cases, a high degree of positive parallax requires that the viewer slightly diverge their vision to track both left and right images. However, one drawback to existing modeling systems is that typical systems cannot account for the outward divergence of human eyes. That is, typical stereoscopic modeling systems (e.g., stereoscopic transformations) assume that the human eye is not capable of outward divergence.
The systems and methods described herein provide techniques for dealing with outward divergence of a viewer's eyes in order to model realistic viewing scenarios.